1. Field of the Invention
The present invention relates to methods of activating and deactivating optical systems. More particularly, the present invention pertains to the method of emplacing or removing a polarizing device used in an optical system that is applied as a neutral density filter, a selective color filter, or a light shutter, to a television pickup camera, to activate or deactivate the optical system, respectively.
2. Description of the Prior Art
In many applications of television, there is a need to switch between a high resolution monochrome television system and a color system. There are also times when neutral density filters must be added to or removed from the television pickup camera, and there are occasions to protect the television camera from damage due to light saturation. Currently, the application of color filters, or a neutral density filter, for a television camera is usually done by mechanical means involving multiple filters. The conversion from a color television system to a monochrome system is performed either electronically or by using monochrome television monitors. In a given case, the techniques may be complex and expensive, and particularly undesirable for use in space applications. The conversion of a television system in space by an astronaut must be accomplished by a method which is relatively troublefree, inexpensive, and simple enough to allow the astronaut to accomplish the conversion despite the hostile environment of space.